Also what I don't think has been addressed in this thread is the question of why there are very few non-white, non-drivers. With the actual driving of a car, you can see why there may not be so many different ethnicities because of motor racing's background and history, and only over generations will we start to see more ethnically diverse grids. However this should not really apply to engineers, technicians, designers, mechanics etc.
There are plenty of great minds in China and India etc, but when was the last time you saw a good head count of people from those regions? Is it a subconscious thing from within the teams? Is it a language thing? Is it because quite a few teams' workstaff are based in the UK? But then that doesn't account for why there are so few black and ethnic minority British workers at those teams.
I can only really say that it is mostly because of the lack of role-models. It is an unfortunate situation in society - do black kids start running track because they see 7/8 runners in the Olympic final are black? Is it because middle class Britain is predominantly white that we see so many white drivers? Is there some ridiculous undercurrent that has been imprinted in past generations that "white kids are smart, black kids are athletic"? I'm not agreeing with that statement by the way, but as a pointer, take a look at American Football. The quarterback, and most prized, position is probably 85% white at the professional level, yet I'm guessing at least 60-70% of all professional American footballers are black. The quarterback role is considered one that needs high intelligence but not necessarily athletic ability, while most other roles require far greater athleticism.
It's an interesting and controversial subject but one that intrigues me. Sorry if I've gone on a bit of a tangent.